Figures and statistics with regard to the white population can only be surmised. In 1650, Virginia, as the oldest of the colonies, may possibly have had 15,000 inhabitants. Stuyvesant's calculation for New York fourteen years later was probably exaggerated when he placed that cosmopolitan people at 10,000. At the time of the Revolution the total population of Maryland, Virginia, and the Carolinas was about 90,000; but the two first colonies had by far the largest proportion, for although Shaftesbury and Locke had worked so hard, the Carolinas had only 4000 settlers all told. The population of East Jersey at the beginning of the eighteenth century was, according to Governor Lewis Morris, "about eight thousand souls";[229] while that of Pennsylvania and Delaware may have been 20,000, at least one-half of whom were English Quakers. Later in the century more exact figures are ascertainable. Virginia in 1724 was still the largest with 65,000; Maryland ran it close with 53,000. Pennsylvania and Delaware had steadily increased owing to immigration to 32,000; and New York, which in 1705 had had 25,000 people, had by 1724 increased to 30,000. New Jersey came next with 26,000, while North and South Carolina lagged behind with 14,000 and 9000 respectively. With so large a population it is only natural that there were various kinds of trade. Tobacco was the staple of Virginia and of Maryland; but by 1701 Virginia tobacco was acknowledged as far superior to that from the Baltimore plantations. South Carolina for the first ninety years of its history relied mainly upon rice, the export of which was encouraged by Sir Robert Walpole in 1730. The colony was now allowed to export rice to any port in Europe, south of Finisterre, provided it was sent in British ships, manned by British seamen. "The result was that the rice of the American plantations beat the rice of Egypt and Northern Italy out of the markets of Europe."[230] After 1741 or 1742, indigo planting became an important industry in the colony, for the seed which was then introduced was found to flourish in the swamps of the South. Iron was worked in Virginia to a small extent. Its value was pointed out by the Company in defence of their charter in 1623: "during these 4 last years that hath been expended in setting up of iron works (the oar whereof is there in great plenty and excellent) above five thousand pounds, which work being brought in a manner to perfection was greatly interrupted by the late massacre."[231] The industry continued throughout the century, but never on a large scale. In Philadelphia a more profitable iron industry existed, while in Maryland in 1749 seventeen iron furnaces were regularly employed. New Jersey made some slight profit from working her minerals, such as iron and copper, but her chief exports were cattle and tanned hides. The exports of Pennsylvania were even more varied, consisting of horses, pipe staves, salted pork and beef, bread-flour,